package com.elong.businesstravel.base.widget;


import android.widget.Gallery;

import android.content.Context;
import android.graphics.Camera;
import android.graphics.Matrix;
import android.util.AttributeSet;
import android.util.Printer;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.view.animation.Transformation;
import android.widget.ImageView;

public class GalleryFlow extends Gallery {
	
	/**
	 * Receives call backs when a new {@link View} has been scrolled to.
	 */
	public interface ViewSwitchListener {

		/**
		 * This method is called when a new View has been scrolled to.
		 * 
		 * @param view
		 *            the {@link View} currently in focus.
		 * @param position
		 *            The position in the adapter of the {@link View} currently
		 *            in focus.
		 */
		void onSwitched(View view, int position);

	}
	
	/**
	 * Graphics Camera used for transforming the matrix of ImageViews
	 */
	private Camera mCamera = new Camera();
	/**
	 * The maximum angle the Child ImageView will be rotated by
	 */
	private int mMaxRotationAngle = 30;
	/**
	 * The maximum zoom on the centre Child
	 */
	// private int mMaxZoom = -120;
	private int mMaxZoom = 0;
	/**
	 * The Centre of the Coverflow
	 */
	private int mCoveflowCenter;

	int lastPosition;

	private boolean setRotateY = false;
	
	private ViewSwitchListener mViewSwitchListener;

	public boolean isSetRotateY() {
		return setRotateY;
	}

	public void setSetRotateY(boolean setRotateY) {
		this.setRotateY = setRotateY;
	}

	public GalleryFlow(Context context) {
		super(context);
		// 是否在滚动是 调用 getChildStaticTransformation方法
		this.setStaticTransformationsEnabled(true);
	}

	public GalleryFlow(Context context, AttributeSet attrs) {
		super(context, attrs);
		this.setStaticTransformationsEnabled(true);
	}

	public GalleryFlow(Context context, AttributeSet attrs, int defStyle) {
		super(context, attrs, defStyle);
		this.setStaticTransformationsEnabled(true);
	}

	/**
	 * Get the Max zoom of the centre image
	 * 
	 * @return the mMaxZoom
	 */
	public int getMaxZoom() {
		return mMaxZoom;
	}

	/**
	 * Set the max zoom of the centre image
	 * 
	 * @param maxZoom
	 *            the mMaxZoom to set
	 */
	public void setMaxZoom(int maxZoom) {
		mMaxZoom = maxZoom;
	}
	
	public void setViewSwitchListener(ViewSwitchListener viewSwitchListener){
		mViewSwitchListener = viewSwitchListener;
	}

	/**
	 * 获得gallery 的中间点
	 * 
	 * @return The centre of this Coverflow.
	 */
	private int getCenterOfCoverflow() {
		return (getWidth() - getPaddingLeft() - getPaddingRight()) / 2
				+ getPaddingLeft();
	}

	/**
	 * 用来获得 子view 的中间点
	 * 
	 * @return The centre of the given view.
	 */
	private static int getCenterOfView(View view) {
		return view.getLeft() + view.getWidth() / 2;
	}

	/**
	 * 
	 * @see #setStaticTransformationsEnabled(boolean)
	 * 
	 *      gallery切换的时候 会调用的方法
	 * 
	 *      child 子view Transformation t
	 */
	protected boolean getChildStaticTransformation(View child, Transformation t) {

		final int childCenter = getCenterOfView(child);
		final int childWidth = child.getWidth();
		int rotationAngle = 0;
		t.clear();
		t.setTransformationType(Transformation.TYPE_MATRIX);

		// 判断是否是中点 中点基本等于 选中的view
		if (childCenter == mCoveflowCenter) {
//			 System.out.println("0000000000000000000000");
			 if(null != mViewSwitchListener){
				 mViewSwitchListener.onSwitched(child, getCenterOfCoverflow());
			 }
			transformImageBitmap(child, t, 0);
		} else {
//			 System.out.println("11111111111111111111111");
			rotationAngle = (int) (((float) (mCoveflowCenter - childCenter) / childWidth) * mMaxRotationAngle);
			if (Math.abs(rotationAngle) > mMaxRotationAngle) {
				rotationAngle = (rotationAngle < 0) ? -mMaxRotationAngle
						: mMaxRotationAngle;
			}
			int scale = mCoveflowCenter - childCenter;
			if(scale > 0){
				//右边
				scale = Math.abs(scale);
			}else {
				//左边
				scale = Math.abs(scale);
			}
			transformImageBitmap(child, t, rotationAngle, scale);
		}
		return true;
	}

	/**
	 * 这个方法在gallery size被更改的时候调用
	 * 
	 * @param w
	 *            Current width of this view.
	 * @param h
	 *            Current height of this view.
	 * @param oldw
	 *            Old width of this view.
	 * @param oldh
	 *            Old height of this view.
	 */

	@Override
	protected void onSizeChanged(int w, int h, int oldw, int oldh) {
		mCoveflowCenter = getCenterOfCoverflow();
		super.onSizeChanged(w, h, oldw, oldh);
	}

	/**
	 * Transform the Image Bitmap by the Angle passed
	 * 
	 * @param imageView
	 *            ImageView the ImageView whose bitmap we want to rotate
	 * @param t
	 *            transformation
	 * @param rotationAngle
	 *            the Angle by which to rotate the Bitmap
	 */
	private void transformImageBitmap(View child, Transformation t,
			int rotationAngle, int scale) {
		mCamera.save();

		final Matrix imageMatrix = t.getMatrix();
		// final int imageHeight = child.getLayoutParams().height;
		// final int imageWidth = child.getLayoutParams().width;
		final float imageHeight = child.getHeight();
		final float imageWidth = child.getWidth();
		// System.out.println("imageHeight : " + imageHeight);
		// System.out.println("imageWidth : " + imageWidth);
		final int rotation = Math.abs(rotationAngle);
		// 在Z轴上正向移动camera的视角，实际效果为放大图片。
		// 如果在Y轴上移动，则图片上下移动；X轴上对应图片左右移动。
		// As the angle of the view gets less, zoom in
//		if (rotation < mMaxRotationAngle) {
//
//			float zoomAmount = (float) (mMaxZoom + (rotation * 1.5));
//
//			System.out.println("zoomAmount : " + zoomAmount);
//
//			mCamera.translate(0.0f, 0.0f, zoomAmount);
//		} else 
		{

			float f = (float) (scale * 0.1f);
			mCamera.translate(0.0f, 0.0f, f);
//			System.out.println("f : " + f);
		}
		// 在Y轴上旋转，对应图片竖向向里翻转。
		// 如果在X轴上旋转，则对应图片横向向里翻转。
		if (setRotateY) {
			mCamera.rotateY(rotationAngle);
		}
		mCamera.getMatrix(imageMatrix);
		
		imageMatrix.preTranslate(-(imageWidth / 2), -(imageHeight / 2));
		imageMatrix.postTranslate((imageWidth / 2), (imageHeight / 2));
		
		mCamera.restore();
		
	}

	private void transformImageBitmap(View child, Transformation t,
			int rotationAngle) {
		mCamera.save();

		final Matrix imageMatrix = t.getMatrix();
		// final int imageHeight = child.getLayoutParams().height;
		// final int imageWidth = child.getLayoutParams().width;
		final int imageHeight = child.getHeight();
		final int imageWidth = child.getWidth();
		// System.out.println("imageHeight : " + imageHeight);
		// System.out.println("imageWidth : " + imageWidth);
		final int rotation = Math.abs(rotationAngle);
		// 在Z轴上正向移动camera的视角，实际效果为放大图片。
		// 如果在Y轴上移动，则图片上下移动；X轴上对应图片左右移动。
		// mCamera.translate(0.0f, 0.0f, 100.0f);
		// As the angle of the view gets less, zoom in
//		if (rotation < mMaxRotationAngle) {
//			float zoomAmount = (float) (mMaxZoom + (rotation * 1.5));
//			// System.out.println("zoomAmount : : ; ::::" + zoomAmount);
//			mCamera.translate(0.0f, 0.0f, zoomAmount);
//			// mCamera.translate(0.0f, 0.0f, 0.0f);
//		}
		// 在Y轴上旋转，对应图片竖向向里翻转。
		// 如果在X轴上旋转，则对应图片横向向里翻转。
		if (setRotateY) {
			mCamera.rotateY(rotationAngle);
		}
		mCamera.getMatrix(imageMatrix);
		imageMatrix.preTranslate(-(imageWidth / 2), -(imageHeight / 2));
		imageMatrix.postTranslate((imageWidth / 2), (imageHeight / 2));
		mCamera.restore();
	}

	/*
	 * 生成view 的顺序 选中的左边 顺序生成 选中的右边倒序生成 解决 重叠顺序的问题
	 */
	@Override
	protected int getChildDrawingOrder(int childCount, int i) {
		int mFirstPosition = getFirstVisiblePosition();
		int mSelectedPosition = getSelectedItemPosition();
		int selectedIndex = mSelectedPosition - mFirstPosition;
		if (i == 0) {
			lastPosition = 0;
		}
		int ret = 0;
		if (selectedIndex < 0) {
			return i;
		}
		if (i == childCount - 1) {
			ret = selectedIndex;
		} else if (i >= selectedIndex) {
			lastPosition++;
			ret = childCount - lastPosition;
		} else {
			ret = i;
		}
		return ret;
	}

	@Override
	public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
			float velocityY) {
		return false;

	}
}
